1. Field of the Invention
The present invention relates to an yttrium oxide containing material suitable for use for components of semiconductor manufacturing equipment.
2. Description of the Related Art
In general, components of semiconductor manufacturing equipment, such as a bell jar, chamber, susceptor, clamp ring, and focus ring, are often used in chemically corrosive atmospheres including a halogen-based gas atmosphere and a high-density plasma atmosphere. Against this background, an yttrium oxide-containing material, which has high corrosion resistance and is less liable to be a contaminant source, has been considered for use in forming those components of semiconductor manufacturing equipment, as disclosed in Japanese Unexamined Patent Application Publication Nos. 11-278935, 2001-179080, and 2006-69843.
A conventional yttrium oxide-containing material is, however, inferior in mechanical characteristics because the three-point bending strength thereof is about 140 to 180 MPa and the fracture toughness is about 0.8 to 1.1 MPa·m1/2. Therefore, when the conventional yttrium oxide-containing material is applied to the components of semiconductor manufacturing equipment, those components can be broken when machined or used, which is disadvantageous in terms of yield, handing, and reliability.
The present invention has been made to solve the aforementioned problem, and an object thereof is to provide an yttrium oxide-containing material with excellent mechanical characteristics.